Heart attack can be triggered by air pollution, to the same extent as other known individual risk factors that include physical exertion, alcohol, and coffee, according to a feature on Medical News Today.
The findings were written by Dr Tim S Nawrot, Hasselt University, Diepenbeek, Belgium and Catholic University of Leuven, Belgium, and colleagues from both institutions, and they appear in an Article Online First and in Lancet. In addition to the findings on air pollution, other factors that could trigger heart attacks to varying extents were identified as anger, positive emotions, sexual activity, cocaine or marijuana use and respiratory infections.
The findings were the result of data from 36 separate studies. The mean participant age for cocaine and marijuana use was 44 years, while that for respiratory infection studies was 72 years. The relative risk posed by each trigger was calculated by the authors, as was the proportion of total heart attacks that may have been caused by that trigger, also known as the population-attributable fraction (PAF).
Air pollution actually increased the risk of triggering a heart attack by 5 percent, compared against a 23 times increased risk brought about by cocaine. However, if the fact that the entire population is exposed to air pollution while only 0.02 percent is exposed to cocaine is considered, it comes out that air pollution can trigger more heart attacks than cocaine.
“Of the triggers for heart attack studied, cocaine is the most likely to trigger an event in an individual, but traffic has the greatest population effect as more people are exposed to the trigger…PAFs give a measure of how much disease would be avoided if the risk was no longer present,” the authors said.